Adsorbent refining of oils



May 19, 1953 H. A. VOGEL ADSORBENT REFINING OF OILS Filed April 21, 1950 75 flTMOJP/IKEE FEED I INVENTOR. HENRY A. VOGEL H'TTORNEK Patented May 19, 1953 t bur h la ou t et.

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The: present inventiomrelates .to; a methodmi treatingaoils which arerglyceridesoi highervfattn acids; and-it has :particulanrelationto-the method oftreatingsuclipile for; purposes. of removing undesirableiconstituents;1such-'asiree fatty acids coloring-matter and-break.-

One object. of the: invention is to provide a process-.ofitreating glyceride oils whereby color-. ing matter,- freedatty acids and breahwconstite uents can be -reduced intamount or even,.elimi nated =:with-a=miniinum of operations:

secondzohject issto iprovide a procesawhereby break; freerfattyu acids and: coloring: matter in glyceride oilsrcan he -reduced or -eliminated with aminimumloss-cf oil.

As third-obj ect is to provide aprocess of treat ing: glyceride drying; oilsor food: oils to obtain products-' which; in the case of the drying= oils; are/suitable for-cooking= to providewarnishes or which; in-the-case of---the;iood -oi-ls,' are suitable for usein the preparation of *salads= or -for otherculinaryuses; without subjecting; the. oils-to alkali refining.

A fourth objectisto prfiyide. a process of treating glyceride oils containing chlorophyll or other coloring agents which are hard; to remove whereby. the content oi; these is reduced,- in; a; highly effective manner;

A-fijth-object. of the; invention is: to; provide a rocessor: treating lyc rideoils. withrefinine adsorbents; whereby, a. high degree: of; efiiciency. of therads rbentasent isobtained.

AESiXt'hzObjGzCt'iS, toprcvideaprocess of treat- 1 1g: slycericier oils. with refining adsorbents in which alminimum amount; ofrthe adsorbent is efiective, to obtain an. adequate degreeof refining.

These-and other objects. ofthe invention will beapparent from consideration of the following specification and the appended claims.

lt is: Well recognizedthat most of'the glyceride oils, and-especially the vegetable oils, arecom posedprimarilyof glycerides of a number of different fatty-acids. However; they also include lesser; amounts of other compounds orcompositions; such as-break constituents; free'fatty'acids and coloringmatter. Many of these secondary components are objectionable in the oil, inasmuchas they oftenprod-uce so-called break, objectionable-color, undue acidity, etc. The break constituents are especially objectionable in many op such as. hydro enat on and; nthe iormation i, lkyd resins due o he Ro prin fe t; pon ata y s. employ d: he, reactions involved.

In order tq refine the natural oils --and-;thus "to eliminate theobjectionabl e constituents; various; methods have heretofore been employede For; example, the oilshave in many casesbeen-subjectecl" to treatment with alkali,= whereby-the break; constituents and; free; fatty acids are re mcvedorat" 1east-to a large extent removede This techniqueis expensive because of the costs ot materialsand-of apparatus" employed inthe operation.- Also; excessive amounts; ofoil are converted into; soaps; and; ar e removedas roots which are of-substantial1y less value" than-the oil; Anothcnn rethoci of treating-insinvolved-steam: ing the oil under vacuum forpurposes oi' reducing odor. The operation also successfullyremoves considerable-amounts of free fatty acids ndm b .conducted-asp. e s wi ll effectivein this respect; I

Coloring matter usually is-not-completely eliminated y; he. oreecine ueraiioneandr Order to reduce the color of the oil it is often necessary to subjectit to-furt-heri treatmentiwith' adsorbent such as fullerfse earth, acid! activatedzclays and adsorbent=-.carbons.= Torarriveat aeproductewhich iscompletelwrefined; that is,; free ofebreak; 10W in freeiattwacids; and of good: color, numerous operations arerthusrequiredtandivery substantial amounts-of- 'oil are losttinthe several stepsr In-a co-pending-application to Roger. Christen: son and Ralph Harpt, SeriahNm 413168; filed July 2-8; 1948;is disclosed an. improved: technique 05 treatingg'l-yceride oils; inwhich. the-.oils: are admixed with a bleachingearth; such-.as-fullerfs earth; and While heated; arev subjectedz to. the action of-1ivesteam at atemp eratureslightly above the-boiling; point-of water, e. at -.to 1130? and at atmospheric pressure;for 10-minut es or; more; Thesteam aridtheearth acting simultaneously, effectively remove breakconstituents greatly enhance 00 0;, and in: manyinstal es substantially reduce the free; acidcontent ofgthe. oil; This process has been in successful ope-ration for some time. It is advantageous in as. he. 1 12. I l ali r fi n the ilemorebreah s ifi entirely ai s required in cases ,where the oil c qntainsexcessive amounts of free fatty acids or break, the amount of ialire i resiz aebe; uqeslitq-semiei The present invention contemplates a process wh ch in certain respects issimilar to that hisclosed; the above indicated application. but is dis in uis ed:- h siI Hl. y h Employment of magnesium silicates and: particularly of synthetic ma nesium. il cat a h v scir m agents.

It has been found that the syntheticmagnesium silicates possess certain substantial advantages over the adsorbents heretofore employed, inasmuch as they are substantially more active in important respects in the presence of steam than other adsorbing agents heretofore employed. For example, the amount of adsorbent employed can be materially reduced, thus lowering the cost of the operation. It would also follow that the filtering operation required to eliminate the adsorbent is facilitated since lesser amounts of material are to be removed from the oil. Furthermore, the volume of oil entrapped 0r entrained with the adsorbent agent is reduced.

Magnesium silicate, even without simultaneous applications of steam, tends to reduce phosphatidic break content. However, proper application of steam greatly accentuates this property. An oil inherently of moderate break content may be rendered break free by application of 3 to 6% of magnesium silicate without steam. However, this same oil when mixed with only 1 or 2% of magnesium silicates and then steamed by the technique herein disclosed will also be rendered break free.

The synthetic magnesium silicates are further characterized by a high capacity for the adsorption of acidic constituents contained in the oil, and their use as the adsorbent agent effectively reduces the free fatty acid content of the treated oil. Furthermore, the synthetic magnesium silicates are found to constitute excellent adsorbents of chlorophyll which is often a minor constituent of glyceride oils and which is very difficult to remove. The chlorophyll if allowed to remain in the oil tends to decompose to a cer- J tain extent and produce a type of discoloration which can only be removed by use of excessive amounts of decolorizing agents, if at all, in the conventional refining operations.

The magnesium silicate component The synthetic magnesium silicates employed in the practice of the present invention are powders or fine granules and may be either hydrated or dehydrated. The preparation of such products which have adsorptive properties, permitting their use as decolorizing agents, has heretofore been described repeatedly in the patent literature as well as elsewhere. The silicates may, for example, be prepared by techniques such as are disclosed in U. S. Patents: No. 2,076,545, No. 2,163,525, No. 2,163,526, No. 2,163,527, No. 2,434,418, No. 2,450,549.

The silicates disclosed in these patents are to be regarded as merely representative of appropriate adsorbents for use in the practice of the invention. Numerous others are contemplated as being within the scope of the invention. One convenient material which is commercially available on the market is sold under the trade name of Magnesol by the Westvaco Chemical Division of Food Machinery and Chemical Corporation. Its composition is given as MgO-2.5 SiO2'I-I2O.

Other activated magnesium silicates of varying magnesia-silica ratios are contemplated as substitutes for this commercial material.

Proportioning of magnesium silicates The magnesium silicates may be employed in varying proportions, dependent upon the activity of the specific magnesium silicate employed and also upon the characteristics of the oil to be treated and the degree to which refining is to be conducted. Oil containing excessive amounts of one or more of the objectionable constituents of course will require larger amounts of the magnesium silicates than others of lower content. As a general rule, it may be stated that .2 to 5% by weight of magnesium silicate based upon the oil treated will be satisfactory. The most economical amount that will give a desired result can be determined in the laboratory by test runs on small samples.

The oils to be treated The oils to be treated comprise any of the common glyceride oils, and notably the vegetable oils which are employed in the paint and food industries. These include linseed oil, soybean 011, cotton seed oil, corn oil, peanut oil and others. These may be unrefined or partially refined. In the case of oils containing large amounts of break, e. g. soybean oil, partial refining, e. g. by water degumming, is advantageous and is usually employed. This operation is inexpensive and it materially reduces the amount of magnesium silicate required in the practice of the present invention by reducing the amount of gum to be removed. Water degumming is a familiar operation and is described in the text Industrial Oil and Fat Products by Alton E. Bailey, copyrighted in 1945 by the Interscience Publishers, Inc., New York, N. Y., pages 501-502 under the heading, 3. Refining by Hydration.

Usually the process of the present invention will be applied to an oil containing less than 0.25% of break in the form of phosphatides, proteins and the like. Soybean oils and other glyceride oils which have been fractionated or separated into portions of higher and lower iodine value by solvent fractionation methods, such as are disclosed in Freeman Patent 2,200,391, are very satisfactory for treatment in accordance with the provisions of the present invention. Either the raflinate oil or the extracted oil as obtained by such process may be treated in accordance with the present invention.

Conditions of operation The equipment may be conventional deodorizing equipment such as is described by Bailey supra, Chapter XVIII, pages 534 to 557.

A glyceride oil containing one or more constituents such as break, color, or free fatty acids, e. g. soybean oil, cotton seed oil, linseed oil, or the like, or one of these oils which has been subjected to fractionation by means of solvents, or which has been water degummed, may be refined by admixing them with an active powder of synthetic magnesium silicate, such as Magnesol, and heating, then steaming them in the apparatus at a temperature within a range of ZOO-250 F. The best results seem to be obtained within a temperature range of 210 or 212 to 225 or 230 F. If the oil is too cold, too much steam is condensed, and if it is too hot the break does not hydrate satisfactorily and is not so effectively eliminated or adsorbed by the magnesium silicate.

The steam at a temperature, for example, approximating that of the oil is preferably blown into the oil and distributed as uniformly as possible. To this end, it may be bubbled in through appropriate distributors disposed near the bottom of a container of oil. Agitators or other devices designed to eiTect more uniform distribution of steam and more thorough contact may be employed in the steaming operation.

The rate of adding steam may vary. If it is slow, a longer time will be required to effect thorthe rafiinate from solvent fractionation.

to aging, may be subjected to oxidative rancidity and other forms of deterioration which are highly objectionable. In order to overcome these difliculties of the solvent extracted raffinates, it is desirable to incorporate anti-oxidants permissible in food products. One very convenient method of incorporating an anti-oxidant or inhibitol or combination thereof involves the addition of a certain amount of unrefined oil to the solvent extracted raffinate. For example, to a rafiinate of soybean oil which is relatively lowin tocopherol there may be added a certain amount of raw or degummed soybean oil or cottonseed oil or other oil containing inhibitol factors. A minor proportion of the raw or degummed oil will usually include an adequate amount of inhibitol factors to provide a product of sufficient stability for most purposes. The invention, for example, contemplates the incorporation of to 25% or even higher percentages of the unrefined oil into the raffinate. Higher proportions of raw oil could be added. but of course as the percentage increases the resultant blend or mixture tends to approach more and more the properties of a nonfraction ated oil.

The technique of the present invention involving the simultaneous treatment of the oil with magnesium silicate and steam at the desired temperature and pressure is applicable to the raflfinate either with or without blending with unrefined oil rich in inhibitols. If stability is not important, the raffinate to be treated need not include additions of anti-oxidants or anti-oxidant-bearing materials. The treatment with magnesium silicate and steam may be made directly to the raifinate. It is also contemplated to add the inhibitor, for example, in the form of unrefined oil or incompletely refined oil containing substantial amounts of inhibitor, before the refining operation. It is an important feature of the treatment with magnesium silicat and steam that inhibitors such as tocopherol are not appreciably afiected in the oil by the treatment. Nearly all of the inhibitol factor remains undisturbed in the oil after treatment. Of course, synthetic inhibitols or anti-oxidants can be added to Such addition can be made either before or after refining of the oil with magnesium silicate and steam. In most instances, however, it is preferable to add the synthetic inhibitor or enrich,- ments thereof to the oil after it has been refined with magnesium silicate and steam.

The use of a second adsorbent in conjunction with synthetic magnesium silicate is also particularly beneficial in the preparation of a light colored break negative oil from whol degummed soya oil. Such a procedure results in an oil meeting the requirements of a varnish-grade refined soya oil. Example II on a subsequent page illustrates this particular application.

It will be noted that the use of a secondary adsorbent of greater decolorizing strength than Magnesol results in a processed oil which is break negative and much lighter in color. In such treatment, one may consider the two adsorbents as complementing each other, with the synthetic magnesium silicate more or less selectively removing the break or phosphatidic constituents and the secondary adsorbent, such as fullers earth or activated clays, removing greater amounts of pigments than the magnesium silicate alone would remove. The amount of the secondary adsorbent used is limited only by practical reasons of economy and the degree of bleaching desired. It is entirely feasible to operate such treatment with combined adsorbents, and it is equally feasible to subject an oil to two separate and distinct treatments, the first being a contacting with the magnesium silicate and steam to remove break, with the second being a contacting with a fullers earth or activated clay and steam to secure very light color.

It may be mentioned that in the best practice of the present invention, the use of a drying gas to effectively remove all water from the steaming is beneficial. Such drying is most efiective when applied to the charge after the steam treatment has been completed and before the oil is filtered for removal of spent adsorbents. The drying results in further color improvement in that it removes water adsorbed by the magnee sium silicate and secondary adsorbent, and makes available fresh adsorbing surfaces in the adsorbent. The filtration rate of a dry oil is also significantly better. than that of a wet oil mixture.

Apparatus In the practice of the invention, various embodiments of apparatus are suitable for conducting the treatment of an oil with steam in the presence of magnesium silicate, Such apparatus can conveniently be purchased from manufacturers of oil treatin equipment.

For purposes of illustration is shown in the single figure of the drawing a simplified embodiment of apparatus.

This apparatus includes a container 8 which may be of any convenient material and of any shape or size. The container may, if desired, be heated by appropriate means, for example, by means of steam .coils or by a steam jacket. However, for convenience of illustration, it is shown as being equipped with electrical heating elements 9. A thermocouple He may be provided for reading temperatures of the oil.

It should also be provided with appropriate cooling, means to facilitate the cooling of the treated oil before it is, filtered. Such cooling means may take the form of external heat exchangers, but for purposes of illustration is shown as a coil of tubing ID with a connection H to a source (not shown) of cooling fluid, e. g, water, that can be circulated through the tube, and an outlet I I a to waste or to a refrigerator or other device designed to recool the fluid. Coil H) can also be used for heating the oil by passing steam through It].

Oil to be treated can be introduced into the container through conduit l2 with control valve {20. The oil may be pre-mixed with the magnesium silicate or, of course, the latter material could be introduced into the oil already in the container by appropriate devices (not shown). The steam at desired temperature can be introduced into the oil through a distributor head indicated at l3 which is joined by conduit M to a source of steam (not shown). This same distributor may further be connected by conduit l6 to a source of inert drying gases, such as carbon dioxide or nitrogen or a mixture of the two, so that oil which has been steamed can be dried before it is cooled. Valves l1 and I8, in lines I4 and I6, permit the selection of steam or drying gas at will as the treating agent, and also permits the regulation of the rate of flow of these media.

To promote the distribution of the steam or the gas in the oil-in the container, an agitator the preliminary treatment with steam and adsorbent agent. The oil as obtained by the foregoing operations could be suitably used in the formulation of paints. It could readily be cooked into a varnish, or compounded into short or long oil alkyds. If desired, the oil could be steam refined under vacuum to provide a product of low acid value. Usually, such further refining is not required.

EXAMPLE II The oil employed in this example again was degummed soya oil which, however, contained some residual break as well as free fatty acids and cooling matter. In the refining operation, 1000 parts by weight of this oil were introduced into the container 8 along with 12.5 parts by weight of magnesium silicate, e. g. Magnesol, and 7.5 parts by weight of an acid activated bleaching earth sold under the trade name of Special Filtrol. This mixture was subjected to steaming as above described. Subsequently, the oil was dried, cooled and filtered. The oil had a greatly improved color, being of a Gardner value of 5.5. The free fatty acid value was .17 and the oil tested break negative. This example illustrates the simultaneous removal of break and orthodox bleaching effects as produced by acid activated bleaching earth incorporated into the oil along with the magnesium silicate. The product was break free and very light of color. These results were obtained in a single step. The losses were very low and yet the product was quite suitable for varnish cooking, heat bodying, or other operations involved in the preparation of paints and varnishes.

EXAMPLE III This example illustrates the application of the principles of the invention to the treatment of crude but partially degummed linseed oil. In the example, 1000 parts by weight of linseed oil admixed with parts by weight of Magnesol was subjected to steam treatment in accordance with the conditions above specified in Example I. The steam treated oil was dried, cooled and filtered to provide a product which was break free. The free fatty acid was reduced by the treatment from an initial value of 1.15% to .95%. A slight reduction of color was simultaneously obtained. However, the product readily bleached upon heat treatment at 550 F. to a Gardnervalue of 5.5. The'initial Gardner value was 11.

EXAMPLE IV In this example, partially degummed linseed oil corresponding to that described in Example III was subjected to the steam treatment in the presence of a mixture of magnesium silicate and acid activated clay. In the example, 1000 parts by weight of the oil were introduced into the container along with 15 parts by weight of Magnesol and 15 parts by weight of Special Filtrol. The steam treatment was conducted in accordance with the disclosure of Example I. The oil product as obtained was break negative, and had a Gardner color of 7. This Gardner value of course could be further reduced by application of heat as for example inbodying or cooking operations employed in making varnishes and alkyd resins.

EXAMPLE V In this example, the oil to betreated was a raffinate of soybean oil resulting from the ex traction of degummed soya oil with furfural asa polar solvent. The oil in a proportion of 1,000 parts by weight was admixed with 15 parts by weight of a synthetic magnesium silicate, e. g. Magnesol, and the mixture was blown at to C. with live steam for a period of 30 minutes, as described in Example I. The oil was initially break positive, had a fatty acid content of .037 and was of a Lovibond color of 50Y;7R. This oil, when treated with magnesium silicate and steam under the conditions above specified, yielded a product which upon drying and filtering was break negative, of a fatty acid content of .014 and of a Lovibond color of 30Y;5R. A portion of this product was steam deodorized under vacuum in accordance with conventional technique. After deodorization, the color of the oil was 5Y;0.5R (Lovibond) and the free fatty acid content was below 0.025%. A second portion of the refind oil was hydrogenated to an iodine value of '70, and was then steam deodorized under vacuum according to conventional techniques. The resulting hardened oil had a Lovibond color of 3Y;0.3R and the free fatty acid content was below 0.025%.

EXAMPLE VI According to this example, 1000 parts by weight of a raffinate of soya oil which had been obtained by fractionation of soya oil with furfural and which contained a small amount of break, coloring matter and free fatty acids was admixed with 15 parts by weight of fullers earth and 15 parts by weight of synthetic magnesium silicate. It was then treated with live steam in accordance with the provisions of the preceding examples. The oil initially contained 043% of free fatty acids and was of a Lovibond color of 50Y;6.5R. Of course, as above stated, the oil was break positive. After treatment with live steam under the conditions specified, followed by drying and filtering, the oil was break negative, of a free fatty acid content of .013, and had a Lovibond color of 7Y;0.6R. Without further treatment, this oil could be deodorized to a salad or cooking oil; hydrogenated and deodorized to a shortening or margarine stock; or could be used in alkyd or varnish preparation.

EXAMPLE VII In this example, 1000 parts by weight of vegetable oil, consisting of 85% by weight of a raffinate of soya oil which had been obtained by fractionation of a degummed soya oil with furfural and 15% by weight of whole degummed soya oil, was admixed with 20 parts by weight of synthetic magnesium silicate, e. g. Magnesol. It was then treated with live steam in accordance with the provisions of the preceding examples. The oil initially contained 0.15% by weight of free fatty acids, was of a Lovibond color of 60Y;8.0R, and the break test was positive. After the oil was treated as above specified, it was dried and filtered. The final oil, upon analysis, was break negative with a free fatty acid content of 04% and a Lovibond color of 35Y;-1.8R. The above refined oil-was hydrogenated to an iodine value of 70, and was then steam deodorized under vacuum to yield a hardened product with a Lovibond color of 4Y;0.4R. The Swift stability (active oxygen method) of the hardened product was hours. a

EXAMPLE VIII In this example, 1000 partsv by weight of vegeearth. It was. then treatedwith live steam in accordance with the provisions of: the preceding: examples. The oil? initially containedl 0.14%. by weight of free fatty acids, was. of a Lovibond; color of 6-0Y;8.0R, and was breakpositive'. After the oil was treatedias' above specified, itwvas dried and filtered; The final. oil, upon analysis, was.

breaknegative and had a free fatty. acid content of 045% and a Lovibond'col'or-ofi12Y;1.0R;.

The above refined oil was hydrogenated to. an. iodine value of '70, and w-as then steam deodorized under vacuum to yield ahardened productwith a Lovibond color of 4Y;:0.3R1J The Swift:

stability (active oxygen method)- of the hardened product was 120- hours.

' EXAMPLE IX In this example; 1'000iparts'- by weight/of a d'egummed soya oil. wasyadmixed: with: parts. by weight of a synthetic magnesium silicate, e; g. Magnesol, and treated. as specified inv Example I; The oil initially containedL0;28% by weight. of free fatty acids, was break positive and. had a Lovibond color of 70Z,';1*5R.. The dried'andfiltered' refined oilwas breaknegative, had a- L0vii bond color of 30Y;6R,and' contained 020% free fatty acid;

A portion of this; refine'doil was steam deodor ized'. under vacuum. in accordance with conven tional technique. After deodorization, the color of theoiliwasdY'; iR Lovibond'and the freefatty acid content was-0.046%- by weight.

As a means of comparison, a portion of the original degummed soya oil was alkali refined and deodorized in accordance with conventional techniques. Thisfina'l deodorized oil had a Lovibond color of 1-5Y;1 .5R, and-a free fatty acid content of 0.020%. Therefined oil-produced, therefore, by the present invention has been shown to yield a deodorized oil with lighter color than one produced from alkali refining.

Av second portion. of the oil refined with synthetic magnesium silicate as specified above was hydrogenated to an iodine value of 70', and then steam deodorized under vacuum by conventional technique. The hardened deodorized oil had a Lovibond color of 3Y;.3R, and a free fatty acid content of 058%. A sample of the alkali refined oi1 previously prepared was similarly hydrogenated and deodorized to yield a product with a Lovibond color of 13Y;1.2R and a free fatty acid content of 0.020% by weight.

The same alkali refined oil was also given a conventional bleach with 1% of acid activated clay, before hydrogenation. After deodorization, this hardened deodorized product had a Lovibond color of 4Y;.4R, and a free fatty acid content of 0.030% by weight. Thi data demonstrates that the refining by means of synthetic magnesium silicate as described above produces an oil which can be processed to a hydrogenated and deodorized product equal to or superior to one which is alkali refined and bleached by conventional techniques.

The oil used in the above series of experiments could also have been prepared as specified in Example II.

The several embodiments of the invention herein disclosed are by way of example. It will be apparent that numerous modifications may be made therein without departure from the spirit 14' of the invention or the scope of the append d claims. 3 I claim:- I; In av process of: refining glyceride oil con.- taining color matter, the stepsof-admixing the oil withsynthetic magnesium silicate having active adsorbing surfaces, then blowing the oil at 200-to 250 F. withlive .steamto adsorb the-coloring matter upon the magnesium: silicate, and filtering' offthe" magnesium silicate with the adsorbed 'coloring matter.

2: In a process of' refining glyceride oils containing chlorophyll as acoloring matter, the steps of admixing the oil with magnesium silicate having active adsorbing surfaces, then blowing the oil tat-200 130 250 F. with live steam. to adsorbthe chlorophyll upon the. magnesium silicate, cooling the oil, and filtering off the magnesiumsilicate with the adsorbed chlorophyll;

3. In a process of refinin glyceride. oils containing break, the steps of admixing the oil with.

magnesium silicate having active surfaces adapted to adsorb: the break, then. blowing the oil at 200 to 250i"F'. with. live. steam to adsorb the break upon the active surfaces, and. filtering off the.

oil with magnesium: silicate having. active adsorbing surfaces, thenblowing the oil. at 200 to 250 F'..w-ith livesteamwhereby toadsorb selectively the free fatty acid'saupon. thesurfaces,cooling. the oil, and. filtering oft the; magnesium silicats. with the adsorbedfree fatty. acids thereupon.

5. In a process of refining glyceride-oils: CD11?- taining. coloring matter; break, and: free. fatty acids, the steps of mixing; the oilswith adsorbent magnesium silicate: having, active; adsorbing surfaces, then blowing th oil for-10' to minutes with livesteam,- at a: rate -of .005 1701213011116. per minute and at a temperature within a range of 200- to 2509713. to adsorb the coloring matter, break, and free fatty acids: from the'surfaces, cooling; the oil, and" removing the magnesium silicate.

6. In a process of refining glyceride oils con-- tain-i'ngbreak, the:-steps.-,of admixing theoil with .2 to 5% by weight of magnesium silicate having active adsorbing surfaces, then blowing the oil with live steam at a temperature within a range of 210-230 F. for a period of 10-90 minutes, drying the oil by blowing it with inert gas, cooling the oil, and filtering off the magnesium silicate to obtain a break-free product.

7. A process as defined in claim 6' in which the product free of break is subjected further to a refining operation to remove free fatty acids.

8. A process of refinin glyceride oils containing break, the steps of admixing the oil with .2 to 5% by weight of magnesium silicate having active adsorbing surfaces, then blowing the oil with live steam at a temperature within a range of 210 to 230 F. and at a pressure approximately atmospheric for a period of 10 to 90 minutes, then drying the oil, and filtering the magnesium silicate therefrom.

9. A process as defined in claim 8 in which the oil treated is degummed soya oil.

10. A process of treating a glyceride oil suitable for food and containing break, free fatty acids and coloring matter, which process comprises admixing the oil with .2 to 5% by weight of magnesium silicate having active adsorbing surfaces, then blowing the oil with live steam at a temperature within a range of 210 to 230 and at approximately atmospheric pressure for a period of 10 to 90- minutes, drying the oil by blowing it with inert gas, cooling the oil and filtering off the magnesium silicate to obtain a break free product, then refining the oil by blowing it with live steam under vacuum to reduce color and free fatty acid content.

11. A process as defined in claim 10 in which the oil treated is soybean oil.

12. The method of preparing a break free glyceride oil of low color and low fatty acid content, which methodcomprises subjecting a rafiinate fraction of glyceride oil, obtained by fractionating with furfural a glyceride oil which comprises a mixture of highly unsaturated glycerides and less highly unsaturated glycerides, to live steam at atmospheric pressure in the presence of magnesium silicate.

13. In the method of preparing a glyceride oil product which is break-free, low in color and free fatty acids but good in resistance to oxidation, from a rafiinate low in tocopherol resulting from the solvent fractionation of a glyceride oil with furfural, the steps which comprise admixing the rafinate with unfractionated oil of relatively higher tocopherol content, adding .5 to by weight of magnesium silicate to the mixture. blowing th mixture with live steam at atmospheric pressure and at a temperature of 210 to 230 F. for to 90 minutes, drying and cooling the mixture, and filtering ofi the magnesium silicate to provide said product.

14. The steps as defined in claim 13 in which the oil of relatively higher tocopherol content is soybean oil.

15. A process as defined in claim 1 in which the oil treated is of a class consisting of soybean oil, linseed oil, and raifinate soybean oil from the extraction of soybean oil with a polar solvent.

16. In a process of bleaching a glyceride oil, the steps of introducing a mixture of synthetic magnesium silicate and acid activated clay into the oil and blowing the oil at a temperature of 210 to 230 F. with live steam to effect adsorption of coloring matter from the oil, then removing the mixture.

17. The steps as defined in claim 16 in which the oil is of a class consisting of soybean oil, liriseed oil, and rafiinate oil from the extraction of soybean oil with a polar solvent.

18. In a process of bleaching a glyceride oil, the steps of blowing said oil in the presence of a mixture of adsorptive magnesium silicate and fullers earth, and at a temperature of 210 to 230 F. to effect color adsorption, then removing the mixture from the oil.

19. In a process of preparing bleached oil of relatively high stability, the steps of blowing with live steam a mixture of soybean raflinate oil from solvent fractionation of soybean oil, and degummed soybean oil, the mixture being at a temperature of 210 to 230 F., and the blowing operation being effected in the presence of a mixture of adsorptive magnesium silicate and fullers earth.

20. The steps as defined in claim 1 in which the mixture of oil and magnesium silicate is further mechanically agitated while being blown, in order to efiect thorough contact of the steam with the oil and the magnesium silicate.

21. The steps as defined in claim 2 in which the mixture is further mechanically agitated while being blown in order to effect thorough contact of the steam with the oil and the magnesium silicate.

22. The steps as defined in claim 5 in which the mixture of oil and magnesium silicate is further mechanically agitated While being blown with steam, in order to effect thorough contact of the steam with the oil and magnesium silicate.

HENRY A. VOGEL.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,377,021 Mumford May 3, 1921 1,891,402 Craise et a1 Dec. 20, 1932 1,959,346 Cummins May 22, 1934 2,454,937 Moyer et al Aug. 5, 1944, 2,475,328 La Lande, Jr July 5, 1949 OTHER REFERENCES Bailey, Industrial Oil And Fat Products, pages 523-524 and 530-532. (1945) Interscience Publishers Inc., N. Y. C. 

1. IN A PROCESS OF REFINING GLYCERIDE OIL CONTAINING COLOR MATTER, THE STEPS OF ADMIXING THE OIL WITH SYNTHETIC MAGNESIUM SILICATE HAVING ACTIVE ADSORBING SURFACES, THEN BLOWING THE OIL AT 200 TO 250* F. WITH LIVE STEAM TO ADSORB THE COLORING MATTER UPON THE MAGNESIUM SILICATE, AND FILTERING OFF THE MAGNESIUM SILICATE WITH THE ADSORBED COLORING MATTER. 